Made a list, taking into account some major conditions* that need to be taken into account when deciding if it’s good enough for your playstyle.
*Minor conditions like ability to gather each 3h were not taken into account because a lot of AWs require that to be used to full potential.
Best AW with no conditions:
Golden Abyss – size matters. It’s small, requires extremely low amount of KPs to level up and gives the same amount of pop as huge and expensive counterpart - Mountain Halls. If leveled up, can provide enough coins to cover your daily needs (for productions).
Best AW with conditions:
Dragon Abbey – undeniably the best AW (beats Golden Abyss) if you have lvl 5 Magic Academy and/or participate in tournaments regularly.
It’s created to be abused. Allows you to bypass game mechanics:
1) removes the need for “mana” buildings, meaning no more waste of space for road connections to low-culture buildings;
2) provides any amount of mana instantly, meaning no more mana decay and no more waiting for mana to accumulate.
Good AWs with no conditions:
Prosperity Towers – it’s better than a workshop. Provides more supplies than EE (see below), if you can collect every 3h at least 5 times per day. Improvement of a spell is a nice bonus.
Endless Excavation – it’s better than a workshop. Requires you to be online once a day to be effective. Nuff said. Primary effect (additional relics) is a joke though.
Mountain Halls – bad version of Golden Abyss. Huge, expensive, but still gives crap load of pop…so… quite “good” AW. Becomes much better if you have magical residences and/or magical workshops, and /or premium culture buildings, and/or a lot of good event buildings with pop and culture: then you can have more manufactories, making its primary effect more…. effective.
Good AWs with conditions:
Martial Monastery/Sanctuary – if you’re a fighter, then it’s a “must have” AW. If you’re not, it’s still good because it’s better than any regular culture building.
Watchtower Ruins – if you list a culture “help” as your first choice, then it’s a “must have” AW. If you’re not, it’s still good because it’s better than any regular culture building.
Crystal Lighthouse/Great Bell Spire - if you list a culture “help” as your first choice, then it’s a “must have” AW. Otherwise, it’s useless. Has a great synergy with Watchtower Ruins (see above).
Tome of Secrets – it’s better than a workshop. Kind of. Falls off late game due to long scouting times, thus becoming worse than Prosperity Towers and Endless Excavation (see above). One of the best early-mid game AWs for sure though.
Decent AW with no conditions:
Blooming Trader Guild – it’s huge, it’s expensive, it’s effectiveness is directly influenced by how many guest race buildings you can build. Think carefully about this one. P.S. You’ll love it more than any other AW during S&D chapter though.
Decent AWs with conditions:
Needles of the Tempest – absolutely useless for players who don’t fight. For those who do, on the other hand, has some questionable value. Archers are used just in 1 tournament as a primary unit. We have 3 different buildings that share training queue, so spending KPs to increase speed of one of them might be a bad idea, because some units will be better in others.
Flying Academy - absolutely useless for players who don’t fight. For those who do, on the other hand, has some questionable value. Mage units are godlike for humans, and absolutely suck for elves. We have 3 different buildings that share training queue, so spending KPs to increase speed of one of them might be a bad idea, because some units will be better in others.
Dwarven Bulwark – absolutely useless for players who don’t fight. For those who do, I’d say it’s a must have AW. If leveled up, replaces need for armories (you’ll basically need armories just to gain orcs), thus saving a lot of pop and culture.
Shrine of the Shrewdy Shrooms – absolutely useless for players who don’t fight. For those who do, I’d say it’s a must have AW as well. If leveled up, replaces need for armories (you’ll basically need armories just to gain orcs), thus saving a lot of pop and culture.
Heroes' Forge* – condition here is its primary effect. Without it, and for players who don’t fight, it’s just bad AW – orcs output is just too small (if not leveled, of course, but you shouldn’t level it first anyway). If you’re a fighter though, turns to be decent AW.
*Theoretically, might be a veeeeeery good AW for players who don’t fight – by leveling it (and by leveling here I mean absolutely dedicating yourself to this AW only), they can get rid of all armories.
Temple of the Toads – absolutely useless for players who don’t fight. For those who do, it’s a generator of ranking points – 2 tournaments use heavy ranged units as a primary unit, and they are the easiest ones. Just don’t forget to fight manually as much as possible.
Elvenar Trade Center – trader already provides more than enough seeds, so primary effect is a joke. Secondary effect is quite good, but only if you’re participating in tournaments and/or have lvl 5 Magic Academy.
Bad AW with no conditions:
Thrones of the High Men – values of effects are just too low for it to be good. Requires heavy leveling to become “decent”.
Bad AW with conditions:
Maze of the Dark Matter – condition here is the ability to build Dragon Abbey (which you should, it being the best AW right now). Huge, extremely expensive KP wise, conflicts with Dragon Abbey…. Just poorly designed AW.